Known utility knifes allow for replacing a dull or used blade with a new blade. However, replaceable blades have exposed cutting edges, which pose a risk to the individual replacing the blade. If the individual lacks sufficient care, they could easily cut themselves on the blade during the replacement operation.
Some effort has been directed toward protecting individuals when replacing blades of various knifes. For example, U.S. Pat. No. 5,342,379 to Volinsky titled “Safety Scalpel” (June 1993) describes a scalpel having disposable blade cartridges for use with a permanent scalpel handle. A scalpel blade in a cartridge remains retracted within housing during a replacing operation. However, when in use the blade can be locked in an exposed position, which is likely useful to a surgeon. Unfortunately locking a blade in an exposed position during use of a utility knife poses a risk to the user because the user could still injure themselves or others. A more comprehensive method of protecting the user is still required.
Another, better approach that would offer greater protection includes integrating a moveable blade cover into a blade cartridge where the cover remains closed when the cartridge is not in use. Such a cartridge can be securely installed within or on a tool handle to provide a solid, useable, and safe cutting tool. The blade cover can be controlled through an actuator that releases or otherwise unlocks the blade cover to allow use of the blade. The cartridge can be inexpensively manufactured, and could be considered a disposable unit.
Furthermore, the handle and cartridge system should provide a foundation for multi-function tool system where many different cartridges can be produced, each with a different type of tool bit (e.g., knife blade, screw driver, pliers, light, etc.). Each cartridge can be installed on a common tool handle.
U.S. Pat. No. 5,933,918 to Wallays titled “Handle with Interchangeable Kitchen Implements” (September 1997) discusses a kitchen utensil having interchangeable implements, many of which have exposed cutting edges. Interestingly, Wallays mentions that a brush utensil could have a separate component that operates as a protective sleeve for a brush, but lacks such protection for cutting implements. One should also note the contemplated interface between the implements and the handle has mechanically many weak points, which can become fatigued through minimal use, and eventually break. Wallays fails to appreciate the each type of implement would likely be better served having a different tool interface more inline with the intended use of the implement.
European patent application EP 0 998 374 to Nabors et al. titled “Foldable Tool with Removable Tool Cartridges” (July 1998) also describes a multi-function tool. However, the Nabors approach merely places multiple tools within a single removable cartridge. The contemplated tools also lack covers and are expensive to manufacture. Should a tool break, the entire multi-tool cartridge would require fixing or replacing as opposed to replacing a single damaged tool bit.
Yet another example of a multi-function tool includes U.S. Pat. No. 5,829,082 to Moreira titled “Multi-Functional Hand Tool” (March 1997). Moreira provides for a tool handle capable of supporting different types of tool attachments. As with the previous references, Moreira lacks any provisions for a tool cover to protect a user during use of the tool.
Further progress was made by U.S. Pat. No. 7,114,824 to Picone titled “Multi-Functional Tool with Interchangeable Adjustable Wrench Head Unit” (May 2004). Picone, describes yet another multi-functional tool where many different types of tool heads (e.g., wrench, light, screw driver bits, wrench sockets, etc.). As with the previous reference, Picone also fails to contemplate that some tool heads require a tool bit cover.
A desirable multi-function tool system should provide for many different types of tools as well as provide for protecting the user of the tool, or for protecting the tool bits with a lockable tool bit cover when the tool is not in use. For example, a tool system should include low cost, possibly disposable, knife blade cartridges having blade covers, or cartridges supporting other types of tool bits. Advantages for such a system become quite clear. Cartridges having lockable tool bit covers aid in preventing users from becoming injured when the tool is in use, when the tool bit is replaced, or when the tool bit is discarded.
Thus, there is still a need for a hand-held tool system having multiple interchangeable tool cartridges where the cartridges can have a tool bit cover that remains closed when not in use.